The purpose of this research program is to study age and intellectual functioning in older adults. Four studies are proposed. The first involves gathering a third wave of data on a sample of 455 elderly who tested with an extensive battery (containing multiple indicators for ten factors) in 1976/7 and in 1983/4. The longitudinal data will be used to evaluate hypotheses concerning changes in structure and level of factor means across three occasions of measurement spanning fourteen years. The second and third studies take advantage of data gathered at two occasions of measurement. Study 2 evaluates the role of terminal decline. The 455 participants (tested at occasions 1 and 2) will be classified as living or deceased, based on information gathered at occasion 3. Existing longitudinal data for these individuals (already gathered) will be used to evaluate whether greater decline over seven years is found for those who are deceased versus those who survive for three variables: vocabulary, arithmetic and symbolic perceptual speed. Study 3 concerns the role of subjective health in intellectual change. Two ratings of subjective health will be employed in path analyses to evaluate prediction (in conjunction with other variables such as sex and education) of change in performance over time for the same three variables described in Study 2. The fourth study employs cross-sectional and longitudinal data gathered during previous funding periods as a part of the Intelligence and memory project. Previous work with path analysis techniques (applied to cross sectional data) has shown a significant relationship between Dyspgoria (one aspect of Depression) and Figural Perceptual Speed. This project will analyze other age sensitive ability factors in both cross-sectional and longitudinal data sets to evaluate the generality of this finding.